The present invention relates to a system of changing the travelling speed of a working vehicle, and more particularly to a system in which a stepless speed-change means is operated by a pedal.
A working vehicle for example a tractor is mainly used for work, such as farming work, which is desired to be performed with the travelling speed of such tractor maintained substantially constant.
To provide such constant speed by a pedal operation may provoke fatigue of the operator foot and such pedal operation itself is not stable. Therefore, it has been difficult to maintain the travelling speed substantially constant.
Furthermore, when a tractor is to be moved from a certain working place to a different one, such tractor is generally moved at a speed higher than the working speed. Therefore, when the tractor speed is to be again reduced to the working speed, it has disadvantageously been difficult to set the tractor speed immediately to the initial working speed.